Manufacture of return connections



July 31, 1923.,

J. LENTE MANUFACTURE OF RETURN CONNECTIONS Filed Sept. 27 1921 Fly. H 2

tain new and reason July or, rat.

JACQUES LENTJE, @3 5" P18, FRANCE,

nnusn, oirnnrs (same),

nssronon 'ro socmrn error i run, a coanr or runner.

I DESCA UT &

MAH'UFAGTUBE 6F RETURN @ONNECTEUNS.

Application filed heptembcr 537, will. Beria'l Ho. 503,6Jt.

W particular of those which are intended to to times united form elements of tubular superheaters.

'lhese connections, which are of U shape, are generally obtained, either in cast iron or cast steel. The elements are also someby direct forging of their end the blowpipe.

and brazing with These difierent means are tar from giving entire satisfaction, and the object of the present invention consists in constructing connections of steel of the desired type iron or cast steel.

All

by the aid of a process which is very simple, their relatively small thickness not being a cause of obstruction in the smoke tubes as is the case with the connections oi cast The accompanying figures, from 1 to will ermit oi the easy comprehension of p 1 the ifierent operations required ror tne process.

Figure l is a longitudinal sectional view of one term of tube from which the return connection is made.

Fig. 2 is a similar view oi the preierred form of tube from which the return connection is made.

Figs. 3 and l are end views respectively of the tubes shown in Figures 1 and 2.

Fig. 5 is a sectional view oi the tube shown in Figs. 2 and 4 after said tube has been bent into [Ll-shape.

Fig. 6 is a vertical sectional view at the means for shaping the U-shaped tube.

The first operation consists in preparing the tubes of suitable length and shape by them by known means, a unitorm extra thickening distributed over their periphery as is shown in Pics l and 3, or

preferably a local extra thickening, as is shown in Figures 2 and l.

lhe tube in Figure 2 for example is afterwards bent into a U as shown in Figure 5, in which the piece is shown in section. The bending of the tube into the shape or the bl is carried out in the second operation on the smallest possible radii which forging permits of. The extreme part corresponds to the reinforced portion of the tube in order to reduce the thinning caused by the bending of the tube into the U and also in order to retain an appreciable thickening.

The third operation, which shapes the connection, is carried out in a matrix of special form shown in Figure 6. The matrix is shown at l and the shaping punch at 2. Two mandrels 3, 3 ensure the calibration of the branches during the shaping operation. in Figure 6, the elbow before it is shaped is indicated by dotted lines and the finished connection by full lines.

Claims.

1. A. process for the manufacture of a return connection, particularly intended to form an element of a tubular superheater, consisting in providing a tube with a thickened portion intermediate its ends, curving said tube into the form of an elbow, plao ing said elbow in a press and exerting pressure on the elbow to shape the metal of the elbow, and inserting mandrels in the ends of said elbow before exerting pressure on the same.

2. A process for the manufacture of a return connection, particularly. intended to form the element of a tubular water heater, consisting in providing a tube with a locally thickened portion intermediate its ends, curving said tube into the form of an elbow, inserting mandrels into of said elbow, and placing said elbow in a matrix and shaping the metal by a punch.

in testimony whereof l afix my siature.

rations were.

the ends lid 

